Chirp Innovations, LLC

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WARNING LETTER
CMS # 731847

October 02, 2026

Dear Mr. Stock:

During an inspection of your firm located in Lehi, Utah from November 18, 2025, through November 21, 2025, an investigator from the United States Food and Drug Administration (FDA) determined that your firm manufactures an Over-The-Counter Transcutaneous Nerve Stimulator TENS & EMS unit branded as the Chirp Halo Wireless Muscle Stimulator. Under section 201(h) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 321(h), these products are devices because they are intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body.

Quality System Regulation Violations
This inspection revealed that these devices are adulterated within the meaning of section 501(h) of the Act, 21 U.S.C. § 351(h), in that the methods used in, or the facilities or controls used for, their manufacture, packing, storage, or installation are not in conformity with the current good manufacturing practice requirements of the Quality System regulation found at Title 21, Code of Federal Regulations (CFR), Part 820.

We received responses from an external consulting agency who provided responses on your behalf, dated December 16, 2025, February 16, 2026, March 15, 2026, April 20, 2026, May 15, 2026, and June 15, 2026, and responses directly from your firm on July 15, 2026, and August 18, 2026, concerning our investigator’s observations noted on the Form FDA 483 (FDA 483), List of Inspectional Observations, that was issued to your firm. We address these responses below, in relation to each of the noted violations. These violations include, but are not limited to, the following:

1. Failure to establish and maintain a quality system that is appropriate for the specific medical devices designed and manufactured as required by 21 CFR 820.5.

For example, you failed to establish procedures for the following requirements of 21 CFR 820:

a. Subpart B – Quality System Requirements. Specifically:
    i. You did not have documentation to establish Management Review, per 21 CFR 820.20.
    ii. You did not have documentation to establish Quality Audits, per 21 CFR 820.22.
b. Subpart C – Design Controls. Specifically, you did not have documentation to establish Design Controls, per 21 CFR 820.30.
c. Subpart E – Purchasing Controls. Specifically, you did not have documentation to establish Purchasing Controls, per 21 CFR 820.50.
d. Subpart J – Corrective and Preventive Action. Specifically, you did not have documentation to establish procedures for Corrective and Preventive Actions, per 21 CFR 820.100.
e. Subpart M – Records. Specifically, you did not have documentation to establish procedures for handling Complaint Files, per 21 CFR 820.198.

The adequacy of the responses dated 12/16/2025, 02/16/2026, 03/15/2026, 4/20/2026, 05/15/2026, 06/15/2026, 7/15/2026, and 8/18/2026, cannot be determined at this time. According to your earlier responses you hired an external consulting agency to assist in the establishment of your quality management system (QMS) and procedures. Your response dated 6/15/2026, however, noted that your firm is now handling these matters internally. Your 4/20/26, 5/15/26, 6/15/26, 7/15/26, and 8/18/26 responses state that you have implemented QMS documents related to ISO 13485:2016 and completed related training of key personnel. Your firm provided evidence that training was conducted on a list of QMS procedures; however, you did not provide the actual procedures governing complaint handling, internal audits, medical device reporting, corrective and preventive action, and returned material authorization. We request that you provide your updated procedures for review in response to this letter.

Unapproved Device Violation(s)
Our inspection and review of your firm’s website (http://gochirp.com) and marketing materials also revealed that the Chirp Halo Wireless Muscle Stimulator is adulterated under section 501(f)(1)(B) of the Act, 21 U.S.C. § 351(f)(1)(B), because your firm does not have an approved application for premarket approval (PMA) in effect pursuant to section 515(a) of the Act, 21 U.S.C. § 360e(a), or an approved application for an investigational device exemption under section 520(g) of the Act, 21 U.S.C. § 360j(g). The device is also misbranded under section 502(o) of the Act, 21 U.S.C. § 352(o), because your firm did not notify the agency of its intent to introduce the device into commercial distribution with major changes or modifications to the intended use, as required by section 510(k) of the Act, 21 U.S.C. § 360(k), and 21 CFR 807.81(a)(3)(ii). For a device requiring premarket approval, the notification required by section 510(k) is deemed satisfied when a PMA is pending before the agency. [21 CFR 807.81(b)] The kind of information that your firm needs to submit in order to obtain approval or clearance for the device is described on the Internet at http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/HowtoMarketYourDevice/default.htm. The FDA will evaluate the information that your firm submits and decide whether the product may be legally marketed.

Specifically, the Chirp Halo Wireless Muscle Stimulator was cleared under K241509 with the following indications: 1)TENS- The device is designated to be used for temporary relief of pain associated with sore and aching muscles in the shoulder, waist, back, neck, upper extremities (arm), lower extremities (leg), abdomen and bottom due to strain from exercise or normal household work activities, and 2) EMS- The device is designed to be used to stimulate healthy muscles in order to improve or facilitate muscle performance.

However, your firm’s promotion of the device for women’s menstrual pain falls outside the scope of the cleared indications for use. Your firm’s promotion of this device for menstrual pain includes, but is not limited to claims or statements such as:

• “Get drug-free pain relief from period cramps on the days your period shows up swinging.”
• “Important Note: Be sure to use the TENS-only settings ("Massage" and "Stretch") to relieve period cramps.”
• Marketing on your webpage: “Halo Menstrual Relief Pad 6-Pack”
• Marketing on your webpage: “Period Pain- Learn what abdominal and period pain is and how to find relief”

Menstrual pain is not caused by “strain from exercise or normal household work activities.” This change therefore describes a new condition that your device is intended to treat. Menstrual pain is caused by involuntary uterine contractions associated with the menstrual cycle, whereas exercise or housework pain usually comes from voluntary muscles becoming sore or strained through physical activity. Marketing this device for the treatment of menstrual pain constitutes a major change or modification in the intended use for which the device lacks clearance or approval. Thus, a new premarket notification is required.

Medical Device Reporting (MDR) Violation(s)
Our inspection also revealed that your firm failed to develop, maintain, and implement written MDR procedures as required by 21 CFR 803.17 for your firm’s Over-The-Counter Transcutaneous Nerve Stimulator branded as the Halo Wireless Muscle Stimulator device.

Specifically, your firm has not established a procedure to evaluate complaints to determine whether they meet Medical Device Reporting (MDR) reporting criteria. Your firm's Vice President of Product confirmed that your firm lacks an MDR procedure and an established process to evaluate complaints for adverse events.

We reviewed your firm’s response and conclude that it is not adequate. Your firm’s July 15, 2026, response indicated that MDR procedures are in place and approved. However, your firm has not provided the actual procedures. Additionally, your firm has not indicated whether a retrospective review of complaints for MDR reportability will be conducted. We request that you provide your MDR procedures in response to this letter.

We note that a device is deemed misbranded under section 502(t)(2) of the Act, 21 U.S.C. § 352(t)(2), if there was a failure or refusal to furnish material or information respecting the device required by or under section 519 of the Act, 21 U.S.C. § 360i, and under 21 CFR Part 803 – Medical Device Reporting.

Your firm should take prompt action to address any violations identified in this letter. Failure to adequately address this matter may result in regulatory action being initiated by the FDA without further notice. These actions include, but are not limited to, seizure, injunction, and civil money penalties.

On February 2, 2024, the FDA issued a final rule amending the device current good manufacturing practice (CGMP) requirements of the Quality System (QS) Regulation under 21 CFR 820 to align more closely with the international consensus standard for Quality Management Systems for medical devices used by many other regulatory authorities around the world. The revised part 820, referred to as the Quality Management System Regulation (QMSR), became effective on February 2, 2026. Your most recent inspection on November 18, 2025 through November 21, 2025 was conducted pursuant to the QS Regulation, which was in effect at the time of the inspection. However, any corrective actions you propose, or implement must be pursuant to the QMSR requirements in effect as of February 2, 2026. For more information on the QMSR please refer to our frequently asked questions webpage: https://www.fda.gov/medical-devices/quality-system-qs-regulationmedical-device-current-good-manufacturing-practices-cgmp/quality-management-system-regulation-final-rule-amending-quality-system-regulation-frequently-asked.

Other federal agencies may take your compliance with the Act and its implementing regulations into account when considering the award of federal contracts. Additionally, should FDA determine that you have Quality System regulation violations that are reasonably related to premarket approval applications for Class III devices, such devices will not be approved until the violations have been addressed. Should FDA determine that your devices or facilities do not meet the requirements of the Act, requests for Certificates to Foreign Governments (CFG) may not be granted.

Please notify this office in writing within fifteen business days from the date you receive this letter of the specific steps your firm has taken to address the noted violations, as well as an explanation of how your firm plans to prevent these violations, or similar violations, from occurring again. Include documentation of the corrections and/or corrective actions (which must address systemic problems) that your firm has taken. If your firm’s planned corrections and/or corrective actions will occur over time, please include a timetable for implementation of those activities. If corrections and/or corrective actions cannot be completed within fifteen business days, state the reason for the delay and the time within which these activities will be completed. Your firm’s response should be comprehensive and address any violations included in this Warning Letter. If you believe that your products are not in violation of the Act, include your reasoning and any supporting information for our consideration as part of your response.

Your firm’s response should be sent via email to CDRHEnforcement@fda.hhs.gov. Please include in the subject line, “CMS Case 731847” when replying. If you have any questions about the contents of this letter, please contact: Shaquenta Perkins at shaquenta.perkins@fda.hhs.gov.

Finally, you should know that this letter is not intended to be an all-inclusive list of the violations at your firm’s facility. It is your firm’s responsibility to ensure compliance with applicable laws and regulations administered by FDA. The specific violations noted in this letter and in the Inspectional Observations, FDA 483, issued at the close of the inspection may be symptomatic of serious problems in your firm’s manufacturing and quality management systems. Your firm should investigate and determine the causes of any violations and take prompt actions to address any violations and bring the products into compliance.

Sincerely,
/S/

For Barbara C. Marsden
Director
Office of Regulatory Programs
Office of Product Evaluation and Quality
Center for Devices and Radiological Health